Front cover of Product Technical Manual

Technical Information

This booklet includes information on testing, installation, design/dimensions and guidance for structural engineers.

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Z Purlins and Girts provide an efficient, lightweight support system for your next construction project. The innovative ‘Z’ design offers greater flexibility in design and installation, driven by significant material savings.

At Donovan Group, we specialise in driving efficiencies in construction. We saw an opportunity to produce the innovative Z design support system, which provides efficiencies throughout the entire Commercial and Industrial building process. 

The ingenious Z design is proven to offer steel weight savings of up to 15%,  making the building process as a whole more productive. By maximising the efficiency of its lapped Z geometry, these support systems require less transportation and reduce installation time, all while providing greater capacity for your new building.

We also offer C section purlins in a range of thicknesses. Contact us today to discuss Z or C purlins for your next portal frame project.

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New Zealand - Technical

John Lawson
+64 21 410 778


New Zealand - Orders

Warren Dingle
+64 21 867 009

 Specifying Z Purlins is an easy way to generate weight savings on industrial and commercial buildings - saving money and reducing our carbon footprint. It's a great win-win. 

Kerry McCollum - Donovan Group Head Engineer

Why Z & C Purlins?

Greater capacity

Less weight

Freight savings

Swift Installation

Cost efficient

Our Purlins and Girts are designed to maximise the efficiency of the increased stiffness and strength of the lapped Z geometry. Its Z shape provides on average a 15% increase in capacity over other simply supported purlins. This diversity suits a wider range of building types and offers more flexibility in your design.

With Z Purlins, your building design can be optimised by either increasing the portal bay widths (reducing the primary structure) or reducing the purlin and girt section sizes or thickness. By reducing the overall purlin and girt component weight, this smart design can achieve weight savings of up to 15% on simply supported designs.

Freight savings are a serious consideration for any business, especially the construction industry. The reduction of up to 15% in weight is directly linked to the amount of transportation required – offering another key saving to your project. The Z Purlins and Girts are also nestable and can be stacked inside one another, thus simplifying the labour process and providing significant time savings.

Installation of our lapped Z Purlins and Girts is an extremely efficient process, with significant weight savings aiding material handling. Additionally, the section process of installation offers a more efficient and safer process due to the ability to ‘nest’ the section whilst lifting or installing.

In portal building construction, weight reduction equals efficiency and subsequently, cost-savings. Our lapped Purlins and Girts are up to 15% more efficient than a simply supported section. The result is a more economical design solution that maximises efficiency, without compromising on strength or structural integrity.

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Contact us for more information about product features, ordering, and related queries.